The present invention relates to a chasing tool for repairing damaged internal threads.
Internal threads, although better protected against mechanical damage than external threads, are frequently damaged by jamming, due to forcible introduction of male components which either have a different pitch, or were misaligned. Also, there often arises the need to remove scale, rust or other encrustations.
It is thus one of the objects of the present invention to provide a chasing tool for repairing internal threads that is effective, inexpensive and easily operated.
According to the invention, the above object is achieved by providing a chasing tool for repairing damaged internal threads, comprising a body provided with a bore; a handle rotatably fitting a portion of said bore and retained therein with one degree of freedom in rotation, said handle being provided over at least part of its length with an internal thread; a substantially cylindrical component, provided with an external thread matching the internal thread of said handle over at least part of its length; a tubular member fixedly attached to said body in a direction substantially perpendicular to the axis of rotation of said handle and opening into the bore of said body; a lever tiltable about a pivot fixedly mounted in said tubular member and providing said lever with one degree of freedom in rotation, said threaded cylindrical component being articulated to one end of the lever and a cutter being articulated to the other end of the lever, said cutter projecting from the tubular member through a window-like opening therein; the arrangement being such that when the handle is rotated in one sense, said cutter is caused to project more from the tubular member, and when the handle is rotated in the other sense, said cutter is caused to project less from the tubular member.
The invention further provides a chasing tool for repairing damaged internal threads, comprising a bar having at least two substantially flat, opposite surfaces; a first arm fixedly attachable to said bar and extending in a direction substantially perpendicular to said bar; a second arm, substantially co-planar with said first arm and slidable along the bar while being guided by said two flat, opposite surfaces of the bar; means for immobilizing said second arm at an optional location along said bar, and at least one cutter articulated to the free end of said second arm.